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In recent years, with the rapid development of the manufacturing industry, shearing machines have become the main piece of plate processing equipment. It has been used more and more widely. Among them, hydraulic swing beam shearing machines are favored by users because of their simple structure, low failure rate, and better cutting quality. During the cutting process, as the tool rest rotates, the cutting angle and knife gap of the swing beam shearing machine will change.

1. Performance Characteristics of Swing Beam Shearing Machines

Swing beam shearing machines are an all-steel welding mechanism, hydraulically driven, vibration relieves stress, and has high strength and good rigidity. Swing beam shearing machines adopt the main oil cylinder (fixed on the wall plate) for downward shearing movement and the return stroke of the nitrogen cylinder, so the hydraulic system is simplified and the operation is more stable. The upper tool post of the shearing machine swings in an arc around a fixed axis during the cutting process. Through the action of leverage, the fulcrum is small, which can increase the life of the cutting blade and the life of the machine. The whole machine has a compact structure and can be infinite. Adjusting the stroke of the upper tool post greatly improves work efficiency.

2. Components of Swing Beam Shearing Machines

A hydraulic shearing machine is generally composed of a frame, a material pressing mechanism, a blade gap adjustment device, a knife holder, and a hydraulic system.

• Frame: The frame part adopts a combined welding overall structure, which has good rigidity. It is mainly composed of left and right columns (wall panels), front wall panels, workbenches, and fuel tanks.

• Material pressing mechanism: The material pressing mechanism is composed of a set of pressing feet installed at the bottom of the frame beam. After the pressurized oil is passed in, the presser foot plunger presses down the steel plate. After the shearing is completed, the presser foot is raised and reset by the spring force.

• Knife gap adjustment device: The adjustment of the upper and lower cutting edge gap is achieved by rotating the clearance adjustment handle to drive the two pinion gears on the shaft to mesh with the sector gears, and then drive the eccentric sleeve on the supporting shaft to rotate.

• Blade holder: The knife holder is a fully enclosed welded structure, which has high torsion resistance and good rigidity. It is connected to the frame by supporting shafts at both ends, and is equipped with a shearing oil cylinder and a return cylinder.

• Cylinder: Two plunger type hydraulic cylinders, which are respectively fixed on the left and right columns. At the same time, there are two cylinders for the return stroke of the tool post. When working, the pressure oil pushes the cylinder plunger to move downwards to make the knife holder downwardly shear, and at the same time compress the nitrogen in the cylinder; when returning, the hydraulic system is unloaded and the nitrogen in the cylinder expands to make the tool holder return. The whole tool rest takes the fulcrum axis as the center to perform reciprocating motion to complete the cutting work.

3. Working Principle of Hydraulic Shearing Machine

After cutting, the shearing machine should be able to ensure the straightness and parallelism requirements of the shearing surface of the sheared sheet and minimize the distortion of the sheet to obtain high-quality workpieces. The upper blade of the shearing machine is fixed on the knife holder, and the lower blade is fixed on the workbench. There is a supporting ball installed on the workbench to prevent the sheet from being scratched when sliding on it. The back gauge is used for positioning the plate, and the position is adjusted by the motor. The pressing cylinder is used to compress the sheet to prevent the sheet from moving during shearing. The guardrail is a safety device to prevent work-related accidents. The return journey generally relies on nitrogen, which is fast and has little impact.

4. Knife Gap and Parameter Adjustment

The cutting rake angle and gap play a very important role in ensuring the cutting quality of the shearing machine. As hydraulic swing beam shearing machines rely on the rotation of the tool holder to achieve the cutting process, the cutting process must have changed in the cutting rake angle and gap.

Specific Steps to Adjust Knife Gap

After the shearing machine has been used for a long time, it is necessary to adjust the blade gap of the shearing machine. The following are the specific steps:

• Remove the lower blade and clean it piece by piece.

• The blade can be used on all four sides, and the selected one side is tightly installed. And check the straightness of the blade in the horizontal and vertical directions.

• Remove the upper blade and clean it piece by piece. In the same way, the blade can be used on all sides, and the selected one side is tightly installed. And check the straightness of the blade in the horizontal and vertical directions.

• The upper blade is fixed and cannot be adjusted. We adjust the blade gap of the shears by adjusting the lower blade.

• Find the left and right screws of the lower blade to increase the clearance, generally on the outermost side.

• Find the left and right set screws of the lower blade to advance the lower blade to narrow the gap. There are locked backup nuts on them. Generally on the inside.

• Loosen the left and right four bolts on the table of the lower blade.

• Manually turn the upper blade down to the proper position, and the operator will start to adjust at the blanking area of ​​the shearing machine.

• Use a feeler gauge to roughly adjust to 0.5 mm from the unoccupied part of the left hand and the upper and lower blades.

• Crank the blade to the middle position and adjust it to 0.5 mm.

• Manually turn the blade upwards to the right position where the upper and lower blades are not disengaged, and the middle position is roughly adjusted to 0.5 mm.

• Turn the upper blade to the proper position and start fine adjustment.

• Use the feeler gauge to fine-tune from the unoccupied part of the left hand and the upper and lower blades to the feeler gauge where three wires can enter and five wires cannot enter.

• Manually turn the blade up to the middle position and start fine-tuning until the three wires of the feeler gauge can enter and the five wires cannot enter.

• Manually turn the blade up to the position where the upper and lower knives are not disengaged on the right side and start fine-tuning until the feeler gauge can enter three wires and five wires cannot enter.

• The above is fine-tuned for the new car to the point that the feeler gauge can enter three wires and five wires can not enter.

Specific Methods to Adjust Parameters

Hydraulic shearing machines are mainly used to cut steel plates of thickness. Commonly used shearing machines are divided into three types: flat shear, rolling shearing machine, and vibration shearing machine. Shearing machines with a cutting thickness of less than 10mm are mostly mechanically driven, and those with a thickness greater than 10mm are hydraulically driven. The following is the specific method of adjusting the parameters.

• The size of the hydraulic shearing machine is mainly related to the back gauge. If you want to have an accurate size, you should adjust the back gauge of the shearing machine, so as to avoid problems and ensure the normal operation of the equipment. Use it to have a good use effect.

• The adjustment of the baffle of the hydraulic shearing machine is realized through the numerical control panel. Therefore, its automatic adjustment mainly depends on whether the numerical control panel is set properly and whether the operation is in place. The general operation is to click on the data input, input the back gauge data, and then press the automatic and then press the start, in this way, the back gauge can be automatically in place.

• When cutting steel plates with hydraulic shears, the cutting thickness is related to the gap between the steel plates. If the steel plate gap is 1 to 3 mm, the adjustment amount is 1 to 2 mm, and if it is 4 to 10 mm, the adjustment amount is 3 to 5 mm. According to the specified shearing thickness, adjust the cutting gap of the shearing machine. It is not allowed to cut two different specifications and different materials at the same time. It is not allowed to cut by overlapping materials. The cut sheet requires a flat surface, and it is not allowed to cut narrow sheets that cannot be compacted. Correct adjustment and use of equipment are required.